Electromagnet



Apr. 10, 1923.

E. M. BOUTON.

ELECTROMAGNET INVENTOR fdyar M Bouzan BY iled Jan. 16,

WITNESSES:

My invention may Patented Apr. 10, 1923.

UNITED STATES PATENT OFFICE.

EDGAR M. BOUTON, OF WILKINSBURG, PENNSYLVANIA, ASSIGNOR 'IO WESTINGHOUSEELECTRIC &; MANUF ACTURI N G COMPANY, A CORPORATION OF ELECTROMAGNE'I.

Application filed January 16,1920.

T all whom it may concern.

Be it known that I, EDGAR M. BOUTON, a citizen of the United States, anda resident of Wilkinsbur in the county of Allegheny and State of lenns'ylvania, have invented a new and useful Improvement inElectromagnets, of which the following is a specification.

a y" invention relates to electromagnets and it is particularlyapplicable to electromagnets that are employed in the operationof'brakes and which are exposed to moisture. T

The object of my invention is to provide an effective, venien'tlyconstructed waterproof electromzignet-for operating a braking device.

eretofore, electromagnets for operating brake mechanisms that aresubjected to moisture have been enclosed in moisture-proof casings.Since it has been the practice to locate the movable armature of suchelectromagnet within the case, it is necessary to encircle theconnecting rod, which operatively 2 connects the armature and the brakemechanism, by a stuffing box'.

According to my present invention, I provide a simple, readilyconstructed waterproof magnet which has no movable parts F2 enclosedwithin the casing and, therefore,

no stuffing box is required. The magnet armatureis entirely external tothe casing and'is' attached to the brake mechanism which it"actu'ates.

best be understood by reference to'the accompanying drawings, in whichFig. 1 is an end View, partially in elevation and partiallyin section,of an electromagnetic' device embodying my invention, and-Fig. 2 isasidevietv, partially in section, 'ofthedevicefshown in Fig. 1.Re'ferringtoFigs. 1 and 2, the' apparatus here shown comprises amagnetizablejmetal- 'liec'asingfl, a core" member: 2'rigidly mountedtherein and an energizing coil 3 suriiouiidin'g the'core member. 'The'casing '1 is provided withfanon-magneticcover 4, preferably of; bronze."An jarin'a'ture member 5, which -way beoperatively connected to adurable, inexpensive and 0011- they are secured to Serial No. 351,847.

- ing 1 by screws9. 'Fromone side of the casing 1 projects a cylindricalportion 10 through which extend the terminals 11 of the magnet coil 3.In addition to their insulating covering, the coil 3 and the terminals11 are insulated from the casing l by waterproof cement 12 which fillsthe space between them and the casing and which conducts the heat fromthem to the casing.

The portion 10 is closed by a steel cap 13 which has two openings letfor the terminals 11 and their watertightinsulating bushings 15; The cap13 is attached to the portion 10 by tap bolts 16. A waterproofconnection of the cap 13 to the rim portion 10*is afforded by a rubbergasket l7, and'a steel washer 18 attached to the inner side of the cap13 by screws 19. The bronze cover 4 is secured to the casing 1 by meansof a clamping ring 20 and screws 21. A rubber gasket 22 ispositionedbetween the casing and the cover. Between the cover 4 and the waterproofcement 12, is placed a layer of felt 23'. A steel disc 24 and a bronzewasher 25 are mounted upon the cover4 and the core member 2 by means ofa tap'bolt 26. A look washer 27 prevents the tap bolt 26 from becomingdisengaged. V

Two opposite sides of the casing l have integral lugs '28 which projectoutwardly so their flat surfaces lie in the same plane as the outer faceof the disc 2 Thesesurfaces attract the corresponding surfaces-"ofthe'armature member 5, when the coils is energized. The lugs 28 and thedisc 24 constitute the pole pieces'of the electromagnet, which, as willbe noted, are external to-the casing.

'The principal path of the magneticflux is through the core member 2'andflthe steel disc 24 to the armature member '5 "and thfib,

' ing parts .waterproof,

through the armature member, the lugs 28 and casing .1, to the coremember 2. A secondary path is through the core member 2, the casing 1,the brake base 7, and the armature member 5 to the core member 2.

A mechanical means for operating the brake armature 5 comprises anarcuate member 29 that is secured to the sides of the casing 1 by tapbolts 30 and is so arranged that the armature member 5 is between it andthe cover 4 and is at right angles to it. In the center of the member 29is a threaded opening 31 for a threaded member 32, which is operated bya hand-nut 33. A taper pin 34 is used to maintain the engagement of thethreaded member 32 with the hand-nut 33. All crevices of the structureare filled with waterproof cement and the casing and external parts ofthe electromagnetic device are coated with shellac or other protectingcomposition.

The electroma'gnet embodying my invention is operated by energizing thecoil 3 to magnetize the core member 2, the casing 1, the brake base 7,the disc 24, and the lugs 28, thereby causing the contact faces of thearmature member 5 to engage the bronze washer 25, thus substantiallycompleting the magnetic circuit. hen the coil 3 is deenergized, thearmature member 5 is re-' leased and returned to the position shown inthe accompanying drawing by the usual springs of the brake mechanism(not shown).

The brake arm may be operated Without the use of electrical energy byturning the hand-nut 33 to rotate the threaded member 32 and thusactuate the armature 5. This arrangement provides means ior manuallyoperating the brake mechanism in case of emergency, such, for example,as that caused by failure of voltage of the source of energy.

My improved device having no moving parts within the casing, is madedust and and, being thus protected.v the have great durability. Themovof the brake mechanism, being unenclosed, may be convenientlyinspected and repaired. The hand-brake mechanism is compact and, beingattached to the casing, permits of convenient operation when electricalenergy is not available.

I have shown a simple and preferred form of my invention, the details ofwhich may be subject to slight modifications. I desire. therefore, thatonly such limitations shall be imposed as are indicated in the appendedclaims.

I. claim as my invention 1. In an electromagnetic braking device, thecombination with an electromagnet, a case for enclosing the saidelectromagnet,

parts will and an external armature member for actuati g a br kemechanism, sa memberbeing for actuating the said ber.

actuated by the said electromagnet, of mechanical means mounted upon thesaid case for actuating the said armature member.

2. In an electromagnetic braking device, the combination with anelectromagnet, a case for partially enclosing the said electromagnet,and an external armature, of mechanical means mounted upon the said casearmature member.

3. In an electromagnetic braking device, the combination with anelectromagnet, a waterproof case for enclosing the said electromagnet,and an external armature member actuated by the said electromagnet, ofmechanical means mounted upon the said case for actuating the saidarmature mem- 4. In an electromagnetic braking device,

the combination with an electromagnet, a

water-proof case for substantially enclosing the said electromagnet, andan external armature member, of mechanical means comprising a rotatablemember mounted upon the said case for actuating the'said armaturemember.

5. In an electromagnetic braking device, the combination with anelectromagnet, a casing for the said electromagnet, and an exing ahand-operated device attached to the said casing for operating the saidarmature member.

6. In an electromagnetic braking device, the combination with 'acoremember, of a coil surrounding the said member, a casing enclosing andpositioning the said member and the said coil, a cement filler placedbetween the said coil and the said casing to tect the said member andthe said coil fromcally connected with the said core,and an externalarmature member actuated by a magnetic circuit comprising the said discand the said lugs.

8. In an electromagnetic braking device,

the combination with a magnetizable coremember, an energizing coil, amagnetizable casing enclosing the said member and the said coil, and. anexternal armature memwh ch i c ua ed by the said member ternal armaturemember, of means comprisand the said casing, of mechanical meanspivotally mounted on the said base and conattached to the said casingfor operating the stituting a portion of two parallel magnetic saidarmature member. circuits, one of which extends through the 9. In anelectromagnetic braking device, said core member and the said casing,and

5 the combination with a magnetizable core the other of which extendsthrough the said 15 member, an energizing coil, a mag'netizable coremember and the said brake base. casing for enclosing and for positioningthe In testimony whereof, I have hereunto said member and the said coil,and a magsubscribed my name this 17th day of De netizable brake base onwhich is mounted cember, 1919.

10 the said casing, of an armature member EDGAR M. BOUTON.

